The chain came off the chainring because the derailleur isn't adjusted correctly. If you don't know how to adjust it, go to your favorite bike shop and have it adjusted. That will solve your problem.
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The Lord is merciful and gracious, slow to anger and abounding in steadfast love. - Psalm 103:8
I am a cyclist. I am not the fastest or the fittest. But I will get to where I'm going with a smile on my face.